Kin recognition plays an important role in social evolution, but the proximate mechanisms by which individuals recognize kin remain poorly understood. In many species, individuals form a kin template that they compare against the phenotype of the conspecific to assess phenotypic similarity (and by association, relatedness). Individuals may form a kin template through self-inspection (i.e. self-referencing) and/or by observing their rearing associates (i.e. family-referencing). However, despite much interest, few empirical studies have successfully disentangled self- and family-referencing. Here, we use a novel set of breeding crosses in the Trinidadian guppy (Poecilia reticulata) to definitively disentangle referencing systems by manipulating exposure to kin from conception onwards. We show that guppies discriminate among their full- and maternal half-siblings, which can only be explained by self-referencing. Additional behavioral experiments revealed no evidence that guppies incorporate the phenotypes of their broodmates or mother into the kin template. Finally, by manipulating the format of our behavioral tests, we show that olfactory communication is both necessary and sufficient for kin discrimination. These results demonstrate that individuals recognize kin by comparing the olfactory phenotypes of conspecifics against their own. This study resolves key questions about the proximate mechanisms underpinning kin recognition, with implications for the ontogeny and evolution of social behavior.

中文翻译：

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孔雀鱼的亲属识别对嗅觉提示使用自我参考

亲属识别在社会发展中起着重要作用，但是人们对亲属识别的近距离机制仍然知之甚少。在许多物种中，个体形成一个亲属模板，然后与亲本的表型进行比较，以评估表型的相似性（并通过关联，相关性）。个体可以通过自我检查（即自我参照）和/或通过观察其养育对象（即家庭参照）来形成亲属模板。然而，尽管有很多兴趣，但很少有经验研究成功地弄清了自我参照和家庭参照。在这里，我们在特立尼达孔雀鱼（Poecilia reticulata）中使用了一套新颖的育种杂交）通过操纵从概念开始的亲属接触来最终确定参考系统的纠缠度。我们表明，孔雀鱼在其同母异父兄弟姐妹之间有区别，这只能通过自我参照来解释。额外的行为实验表明，没有证据表明孔雀鱼将其亲兄弟或母亲的表型纳入亲属模板。最后，通过操纵我们的行为测试的格式，我们表明嗅觉交流对于亲属歧视既必要又足够。这些结果表明，个体通过将同种异体的嗅觉表型与自己的嗅觉表型进行比较来识别亲属。这项研究解决了有关支持亲属识别的近端机制的关键问题，这些机制对个体的发生和社会行为的演变产生了影响。